#define _CRT_SECURE_NO_WARNINGS  1
#include<stdio.h>
int main()
{
    int n = 0;
    scanf("%d", &n);
    int i = 0;
    double  sum = 0.0;
    int arr[10] = {0};
    for (i = 0; i < n; i++)
    {
        scanf("%d", &arr[i]);
        if (arr[i] > 60)
        {
            sum += 0.2;
        }
        else
        {
            sum += 0.1;
        }
    }
    printf("%.1lf", sum);
    return 0;
}